Sighting instrument.



J. E. LOGAN.

SIGHTING' INSTRUMENT.

APPLICATION man SEPT.H, 191s;

' Pafented NW. 20, 1917-.

IZZZ67Z$0 7" (707272 E. Laya/a @MQ MM,

' JOHN E. LOGAN, or KANSAS CITY, MISSOURI.

-t an on SIGHTING INSTRUMENT.

raeeseo.

Specification of Letters Patent.

Patented Nov. so, 1917.

' Application filed September :11, 19 16. SerialNo. 119,450.

, To all whom it may concern:

'Be it known that I, JOHN E. LOGAN, a

citizen of the United States, residing at a KansasiCity, in the countyof J ackson and State of Missouri, have invented certain new and useful Improvements in Sighting Instruments, of which the following is a specification.

poses, it is intended more particularly for My invention relates to sighting instruments, and while adaptable to other puruse on all kinds of air craft in accurately locating objects, so that bombs "and other mis siles can be dropped thereon.

By the, use of my device, an avlator can accurately lOoate enemy troops, guns, roads,

I Y bridges, ships, etc.,. which he may (lesire to destroy by dropping various kinds ofbomb's thereon, as he can determine by the aid of of Fig. 1.

the instrument whenhe isexactly over the target. w v

In order that the invention may be fully understood, reference'will now be made to the accompanying drawing, in which:

Figure 1 is a side elevation of the sight ing instrument.

Fig. 2 is a vertical section on line II'II Fig. 3 is a plan view of the instrument.

Fig. 4 is a detail inverted plan view of a sighting tube, constituting an important feature of the invention. a In carrying out the invention, I employ a pendant sighting tube 1 of sllghtly conical form with the large terminal'downward and weighted with a suitable annular we ght 2 to hold said tube 1 in vertlcal position.-

Cross wires 3 and a are located at the lower portion of the tube 1 to accurately determine when said tube is directly over a target. The wire 3 is, preferably, arranged parallel with the axis extending from the front to the rear of the air craft, so that a long object upon the ground like a railroad, for instance, can be readily followed by keeping said wire 3 parallel therewith.

The upper portion of the tube 1' is provided with a tubularshank 5, formed lntegral with an eye-piece 6 having a small aperture 7 in its upper portion arranged in axial alinement with the intersectmg portions of the cross wires 3 andfl. The sides of the eyepiece 6 are of spherlcal formation and fit within a socket 8, having a pa1 r of oppositely-disposed trunnions 9 prO eCtmg into vertical slots 10 in opposite sides of saideye piece 6, as disclosed by Figs. 2 and 3. v V The trunnions 9 are, preferably, arranged parallel to the'cross wire .t-to prevent the sighting tube 6 from rotating axially andthrowing the cross wire 3 out of parallelism with theaxis of theair' craft. However, the eye-piece 16 hassuflicient freedom of movement in the socket 8 to permitthesighttube 1 to move laterally in any direction or gyrate about its axis independently of the socket-8, Thus it will be understood that the tubel is held in vertical position by the weight .2, irrespective of the position that the socket 8 may assume, within certa1nl1m= itations' The socket 8 is embraced by a rubber or other suitable cushion 11 to protect the eye from contact with the hard surface of either the eye-piece Gorsaid socket'8, Said,

cushion 11 also fits closely around" the eye and'excludes light from the interior of the socket .8, thereby rendering the sight throughtheaperture 7 very distinct." An arrow at isfengravedor otherwise formed on the upper surface of the eye-piece 6 and' ar-t ranged directly over and parallel with the cross wire 3,.so that the general position of the latter'can be readily ascertained without looking through the sight opening 7'.

12 designates a cap formed integral with,

or otherwise suitably secured to the lower portion of the socket 8 and provided with oppositely-disposed bayonet slots 13, to receive two diametrically-opposed pins 14 on the upper end of a conical wind shield 15. As disclosed by Fig. 2, the conlcal wind shield 15 surrounds the sighting tube 1 and thus protects the same from air pressure when an air craft equipped with the instrument is traveling at high'speed. The lower end of the wind shield 15 is closed by a glass disk 16, to prevent the wind from blowing upward through the sighting tube 1 and affecting the eye ofthe operator as he looks through, said sighting tube 1 and also from swaying said sighting tube.

The wind shield'15 is reliably secured in any'suitable manner to the air craft within convenient reach of theaviator,so that he may steer the craft and also look through the sighting tube 1. Lugs 17 are fixed to opposite sides of the wind shield 15 to afford means for attaching braces thereto to furs ther secure the wind shield to the air craft.

In practice, the wind shield '15 is secured to the air craft, preferably, at rightangles to the axis thereof when the air craft occupies a horizontal position. T hen when said air craft tips in any direction,the fiaring sides of the wind shield will not contact the sighting tube 1, which at all times is held in perpendicular position by the weight 2. The wide lower portion of the wind shield 15 and the comparatively wide lower end of the sighting 'tube 1 afford abroad field of vision, so that the air craft does'not have to be directly over a target in order to be clearly visible to the eye of a person looking through the sight opening ,7. If it is desired to follow a road the air craft is first brought approximately over said road through the aid ofthe arrow to. Then by looking through the sight opening 7 the aviator can accurately follow the road by keeping the cross wire 3 directly over said road. If a bridge or other target along the road is to be destroyed the aviator can accurately determine when he is directly over said target when the intersecting portions of the cross wires 3 and 4 are in vertical alinement with said target and he can accordingly drop bombs and other missiles with the greatest accuracy.

Should the aviator be compelled to de- "scend in the rear of the enemy lines where 'he is likely to be captured, he can readily detachthe cap 12'with the sighting tube 1 from the wind shield 15, owing to the bayonet slots '13, and throw the detached parts ,into a stream or other place where they are not likely to be found andthus the construc tion of the instrument maybe kept secret from the enemy.

From the foregoing description, it is apparent that I have produced a comparatively simple and inexpensive sighting instrument, and while Ihave shown and described the preferred form of my invention, I reserve topics at the right tomake such changesfin the construction, proportion, and arrangement of parts as properly fall within the spirit and scope of the claims.

Having thus described my invention, what I claim and desire to secure by Letters Patobject.

2. A sighting device for aeroplanesand the like consisting of an outerfcas ing,'a glass covering for the botton'r'of the casing to exclude air currents, meansborne bythecasing to rigidly secure-same 'to an aeroplane, a sighting tubein th'e casing, means to close the top end of thecasing to'ex'clude air currents, means to movably support "said tube from thet'op'of the casing, an eye piece connected to said tube, and a cushionmemberericirclingthe 'eye piece and extending upwardly beyond the same to "engage the head of the user in surrounding "relation to the users eye. I

In testimony whereof I aifix r'ny'signature, in the presence of 'two witnesses.

JOHN E. LOGAN.

Witnesses:

F. G. FISCHER, L. J. FISCHER.

this patent may be obtained for five centseach, by addressing the fiomm issioner of Eatenta,

Washington, 19.. c3 

